Gonads annual development of Kelee shad, <Emphasis Type="Italic">Hilsa kelee</Emphasis> (Cuvier, 1829) from the coastal waters of Pakistan and its spawning ecology

Annual reproductive cycle and spawning ecology of Kelee shad, Hilsa kelee were studied. The sex ratios did not exhibit as 1: 1; whereas 69.19% were females. On the basis of histological examination, the maturity of female gonads of H. kelee was categorized in eight developmental stages: immature, developing, fully developed, hydrated, running ripe, partially spent, spent and post spawning. Whereas males of this species were categorized in five developmental stages: immature, developing, ripe, partially spent and spent. This fish is repeatedly spawner and spawns twice per year: in April to June and August to October. The values of exponent b in the length weight regressions (W = al ^b ) slightly varied in males b = 3.133, R ² = 0.96 and P < 0.01 and females b = 3.143, R ² = 0.95 and P < 0.001. The linear regressions of length-weight relationships were significant for both males and females.     

Study on the Host–Parasite Relationship of Parapenaeopsis stylifera (H. Milne Edwards) (Decapoda:Penaeidae) and Parapenaeon japonica (Thielemann); (Isopoda:Bopyridae)

Thirteen species of penaeid shrimps, namely, Fenneropenaeus merguiensis, F. penicillatus, F. indicus, Penaeus semisulcatus, Metapenaeus affinis, M. monoceros, M. brevicornis, M. stebbingi, Parapenaeopsis stylifera, P. hardwickii, P. sculptilis, Parapenaeus longipes and Metapenaeopsis stridulans were examined in the present study. With the exception of Fenneropenaeus merguiensis and Parapenaeopsis stylifera no other shrimp species were found to be infected with bopyrids, the infection rate being 0.21% in F. merguiensis and 1.22% in P. stylifera. No marked change was observed in weight of the shrimps infected by bopyrids, however, a single male shrimp infected with bopyrid possessed a female like rostrum. All the infected male and female shrimps were found to be sexually immature.